1. Field of the Invention
The present invention relates to an anti-bacteria agent which is suitable for protecting foods from contamination with bacteria, in processed foods manufacturing industry, in food restaurant industry, and at home, and for disinfecting, sterilizing or pasteurizing in medical industry and medical welfare industry, and relates to a method for desalinating and purifying sea water and river water, and further to a method for washing or cleaning with use of water purified with this anti-bacteria agent.
2. Description of Prior Art
Chemical compound(s) of chlorine have been used as a general anti-bacteria agent. However, they sometimes generated trihalomethane in a treatment of waste water and/or generate dioxin in an incinerating or burning treatment. As examples of anti-bacteria agents, which have been used as a food additive in farming and fisheries or marine products industry, there are synthetic anti-bacteria agents, such as sulfamizin, carbadox, or the like, as medicines for animals. However they must be strictly controlled, in particular, in residual value thereof to be less than a standard value, from a view point of safety of foods.
Therefore, the anti-bacteria agents made from natural materials as ingredients, rather than the anti-bacteria agents of chemical compound(s) mentioned above are required, in particular, in a field of treating foods which have a possibility to be taken inside the human body through a mouth. For example, a report xe2x80x9cAn Effect of Green Tea On O-157xe2x80x9d was published by the group of Prof. Tadakatsu Shimamura, the medical department of Showa University, and attracted attention of many consumers. After this publication, catechin of tea, though it was conventionally used as a food additive, has come into wide use.
The catechin of tea, attracting attention as an anti-bacteria agent made from a natural material, must be extracted from green tea as an ingredient. Therefore it is not suitable for mass production. Accordingly, a new anti-bacteria agent is required, which is made from a natural material as an ingredient, is harmless when absorbed in the human body, can be produced in mass production with low cost, and shows a further high anti-bacteria effect.
In particular, an anti-bacteria agent which is made from a natural material and is harmless when absorbed into the human body, is considered also to have an effect on purification of water. Hereinafter, there are listed examples or cases now in issue.
First, the desalination of sea water can be listed. In the countries of the Middle East, freshwater is obtained from sea water through a reverse permeable membrane method, a distillation method, a refrigeration method or an electric dialysis method, in general. When salt is removed from sea water in this manner, bacteria can easily propagate. Therefore an anti-bacteria agent of Cr group or Cl group, is added to prevent the propagation of bacteria. However, the agent of the Cr group or Cl group is extremely harmful to the human body, and a danger of producing cancer cannot be denied.
Second, the purification of river water can be listed. In river water into which drainage by human life (organic matter) flows, the BOD value is high, and it generates bad smell.
Third, washing or rinsing of agricultural products can be listed. To agricultural products after a harvest, an insecticide sometimes adheres. As a result of this, after agricultural products are washed with a synthetic detergent, they are rinsed with water for general use (i.e., water from a water supply or from rivers), in order to wash such insecticide away. However, since ordinary water is poor in anti-bacteria effect or power by itself, there is a possibility that bacteria propagates on the surface of agricultural products until they reach general consumers.
For solving the problems mentioned above, there is provided an anti-bacteria agent made from shell. An anti-bacteria agent, according to the present invention, is obtained by heating a shell in an atmosphere of inactive gas and burning the shell under the temperature which finally reaches 700xc2x0 C.-2,500xc2x0 C.
As shells, a surf clam is the most preferable, since it is recognized to have sterilizing power against general bacteria. However it may be any one of an oyster, a scallop, a clam, a turban shell and a snail, if it is burned. By burning, the shell itself comes to be porous, therefore a contacting area is increased, thereby remarkably improving sterilizing or disinfecting power.
In particular, a shell powder of a surf clam, by burning in an atmosphere of inactive gas, shows a strong and continuous property of anti-bacteria against germs or bacteria, such as Escherichia coli O-157 or the like, even if it is added only in a small amount. It is also a natural material which mainly contains calcium, therefore it is safe for the human body. In addition, in a case where it is disposed, it never contaminates air, water, or soil. It also brings the effect that shells, which were too much to be managed as waste conventionally, can be utilized effectively.
If the anti-bacteria agent mentioned above is crushed to have a maximum particle diameter equal to or less than 100 xcexcm and have a mean particle diameter from 1 xcexcm to 50 xcexcm, it can be easily dissolved into water (in particular, into warm water), thereby enabling to further improve its anti-bacterial effect.
The burned shells made from natural material or natural ingredient are described in No. 218 of the list of existing additives, which is defined in the revised version of the Food Hygiene Act and the Nutrition Improvement Act as burned calcium (which mainly contains calcium compounds obtained by burning shells or the like). These are officially recognized to be safe for the human body.
Accordingly, regarding an anti-bacteria agent according to the present invention, it is preferable for it to be used for protecting foods from contamination by germs or bacteria in the food service or food restaurant industry or at home, and for sterilization, pasteurization, or disinfection in the medical industry or medical welfare industry.
The anti-bacteria agent of the present invention, which is applied to desalination, is made to be in contact with freshwater obtained from sea water by using any one of the reverse permeable membrane method, the distillation method, the refrigeration method or the electric dialysis method.
As a result of such structure, it is possible to remove or remarkably reduce the amount of a disinfectant or germicide of the Cr group or Cl group which is added to freshwater after being obtained from sea water.
According to the present invention, which is applied to purification of river water, the above-mentioned anti-bacteria agent is filled into a net (including a case through which river water permeates), and the net is laid in a river.
The burned shells, in addition to the anti-bacteria function, come to be porous. Therefore bacteria which decomposes organic matter propagates on the surface thereof, thereby promoting purification of river water. Further, if river water is increased in a degree of an acidity thereof, the burned shells are dissolved into the river water, so as to maintain a pH value within the most suitable range.
According to the present invention, which is applied to the washing of agricultural products, agricultural products such as vegetables, fruits or the like, are rinsed with water contacted with the above-mentioned anti-bacteria agent after being washed with a synthetic detergent.
As a result of this structure, it is possible to suppress propagation of germs or bacteria on the surface of such agricultural products for a long time period.